U.S. patent application number 14/820862 was filed with the patent office on 2015-11-26 for image pickup device.
The applicant listed for this patent is FUJIFILM Corporation. Invention is credited to Shuji ONO.
Application Number | 20150338606 14/820862 |
Document ID | / |
Family ID | 51391012 |
Filed Date | 2015-11-26 |
United States Patent
Application |
20150338606 |
Kind Code |
A1 |
ONO; Shuji |
November 26, 2015 |
IMAGE PICKUP DEVICE
Abstract
An image pickup device includes a photographing optical system
having a central optical system disposed at a central region and a
circular optical system disposed at an outer portion of the central
optical system which are arranged along the same optical axis, a
directional sensor having plural pixels including two-dimensionally
arranged photoelectric conversion elements, the directional sensor
including plural pixels for selectively receiving light beams of
light fluxes which are incident via the central optical system and
the circular optical system by applying pupil division, an image
readout device that acquires from the directional sensor each of an
image signal representing a first image received via the central
optical system and an image signal representing a second image
received via the circular optical system.
Inventors: |
ONO; Shuji; (Tokyo,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUJIFILM Corporation |
Tokyo |
|
JP |
|
|
Family ID: |
51391012 |
Appl. No.: |
14/820862 |
Filed: |
August 7, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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PCT/JP2014/050116 |
Jan 8, 2014 |
|
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14820862 |
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Current U.S.
Class: |
348/322 |
Current CPC
Class: |
H04N 5/232933 20180801;
G02B 13/02 20130101; G02B 13/18 20130101; H04N 5/232 20130101; H04N
9/04557 20180801; H04N 5/2353 20130101; G02B 13/04 20130101; G02B
13/0015 20130101; G03B 15/00 20130101; H04N 5/2259 20130101; H04N
5/378 20130101; H04N 5/2254 20130101; H04N 5/2351 20130101; G02B
17/0808 20130101; H04N 5/3696 20130101; G02B 15/00 20130101; G02B
3/0037 20130101 |
International
Class: |
G02B 13/00 20060101
G02B013/00; H04N 5/378 20060101 H04N005/378; H04N 5/225 20060101
H04N005/225; G02B 3/00 20060101 G02B003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 21, 2013 |
JP |
2013-032100 |
Claims
1. An image pickup device comprising: a photographing optical
system having a central optical system disposed at a central region
and a circular optical system disposed at an outer portion of the
central optical system which are arranged along the same optical
axis; a directional sensor having plural pixels including
two-dimensionally arranged photoelectric conversion elements, the
directional sensor including plural pixels for selectively
receiving light beams of light fluxes which are incident via the
central optical system and the circular optical system by applying
pupil division; and an image readout device that acquires from the
directional sensor each of an image signal representing a first
image received via the central optical system and an image signal
representing a second image received via the circular optical
system, wherein the directional sensor having directional
characteristics depending on pupil shapes of the central optical
system and the circular optical system at an image surface position
is used, wherein the directional sensor has a microlens serving as
a pupil division device, the microlens dividing a pupil image and
each divided pupil image entering the pixel, and the number of the
pixels allocated to one microlens decreases as an image height
increases.
2. The image pickup device according to claim 1, wherein a size of
each pixel in the directional sensor is identical, and a size of
the microlens used decreases as the image height increases.
3. The image pickup device according to claim 1, wherein a size of
the microlens is identical, and a size of the pixel in the
directional sensor increases as the image height increases.
4. The image pickup device according to claim 2, wherein the
central optical system has larger image forming magnification at
the central region and smaller image forming magnification at a
periphery side.
5. The image pickup device according to claim 2, wherein the
circular optical system has smaller image forming magnification on
an inner diameter side and larger image forming magnification on an
outer diameter side.
6. The image pickup device according to claim 1, wherein the
directional sensor has a light shielding mask serving as a pupil
division device, and the light shielding mask having an opening
shape depending on pupil shapes of the central optical system and
the circular optical system at an image surface position is
used.
7. An image pickup device comprising: a photographing optical
system having a central optical system disposed at a central region
and a circular optical system disposed at an outer portion of the
central optical system which are arranged along the same optical
axis; a directional sensor having plural pixels including
two-dimensionally arranged photoelectric conversion elements, the
directional sensor including plural pixels for selectively
receiving light beams of light fluxes which are incident via the
central optical system and the circular optical system by applying
pupil division; and an image readout device that acquires from the
directional sensor each of an image signal representing a first
image received via the central optical system and an image signal
representing a second image received via the circular optical
system, wherein a first image circle for the central optical system
is different from a second image circle for the circular optical
system, and the directional sensor has the pixel for selectively
receiving light by applying the pupil division disposed at only a
region where the first image circle and the second image circle
overlap one another.
8. The image pickup device according to claim 1, wherein the
central optical system has wider angle as compared with the
circular optical system.
9. An image pickup device comprising: a photographing optical
system having a central optical system disposed at a central region
and a circular optical system disposed at an outer portion of the
central optical system which are arranged along the same optical
axis; a directional sensor having plural pixels including
two-dimensionally arranged photoelectric conversion elements, the
directional sensor including plural pixels for selectively
receiving light beams of light fluxes which are incident via the
central optical system and the circular optical system by applying
pupil division; and an image readout device that acquires from the
directional sensor each of an image signal representing a first
image received via the central optical system and an image signal
representing a second image received via the circular optical
system, wherein the central optical system has wider angle as
compared with the circular optical system, wherein the circular
optical system has a catoptric system for reflecting the light flux
two or more times.
10. The image pickup device according to claim 9, wherein the
directional sensor is positioned on an object side with respect to
the catoptric system which first reflects the light flux.
11. The image pickup device according to claim 1, wherein the
central optical system and the circular optical system share a part
of the optical system.
12. The image pickup device according to claim 1, comprising a mode
switcher that switches between a first imaging mode and a second
imaging mode different in a focal length from each other, wherein
the image readout device acquires from the directional sensor the
image signal representing the first image obtained by receiving
light via the central optical system when the mode switcher
switches to the first imaging mode, and acquires from the
directional sensor the image signal representing the second image
obtained by receiving light via the circular optical system when
the mode switcher switches to the second imaging mode.
13. The image pickup device according to claim 12, wherein the mode
switcher has a switching function to switch to a hybrid imaging
mode for performing two kinds of imaging different in the focal
length, and the image readout device simultaneously acquires from
the directional sensor the image signal representing the first
image obtained by receiving light via the central optical system
and the image signal representing the second image obtained by
receiving light via the circular optical system when the mode
switcher switches to the hybrid imaging mode.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of PCT International
Application No. PCT/JP2014/050116 filed on Jan. 8, 2014, which
claims priority under 35 U.S.C.sctn.119(a) to Japanese Patent
Application No. 2013-32100 filed on Feb. 21, 2013. Each of the
above application(s) is hereby expressly incorporated by reference,
in its entirety, into the present application.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an image pickup device, and
particularly relates to an image pickup device capable of
simultaneously acquiring a wide angle image and a telephoto
image.
[0004] 2. Description of the Related Art
[0005] In the past, there has been proposed a dual focal length
optical system in which a wide angle lens is disposed at a central
region and an annular telephoto lens is disposed at an outer
portion of the wide angle lens along the same optical axis (FIG. 1
in PTL 1: National Publication of International Patent Application
No. 2011-505022). The annular telephoto lens of this optical system
has a reflective mirror type lens configuration including two
reflective mirrors, which provides a compact configuration of a
telephoto lens having a long a focal length. Image formed positions
of the wide angle lens and telephoto lens in this optical system
are designed to be at the positions different from each other in
the optical axis direction, and image pickup elements are
separately disposed at the respective image formed positions.
[0006] There has been proposed an optical device which includes a
wide angle objective optical system, a telephoto objective optical
system, and a common optical system through which a light ray
having passed through either of the objective optical systems
passes through in common, and has a reflective member selectively
introducing any of subject light beams taken in by the plural
objective optical systems into the common optical system (PTL 2:
Japanese Patent Application Laid-Open No. 2009-122379).
[0007] Then, the reflective member is made movable so as to
introduce the subject light taken in by the objective optical
system that is any one of the wide angle objective optical system
and the telephoto objective optical system into a common image
pickup element via the common optical system.
[0008] There has been proposed an image pickup device in which
subject light beams passing through different regions on an imaging
lens are subjected to pupil separation and made incident on pixels
on an image pickup element corresponding to the different regions
on the imaging lens to simultaneously capture plural images
corresponding to the subject light beams having been subjected to
the pupil separation (PTL 3: Japanese Patent Application Laid-Open
No. 2012-88696).
SUMMARY OF THE INVENTION
[0009] In the optical system disclosed in PTL 1, the wide angle
image and the telephoto image imaged respectively through the wide
angle lens and the telephoto lens are acquired from the separate
image pickup elements disposed at the positions different from each
other in the optical axis direction, which causes a problem that
the size reduction and cost reduction of the device are
difficult.
[0010] In the optical device disclosed in PTL 2, the reflective
member (reflective mirror) is made movable to select any one of the
objective optical systems of the wide angle objective optical
system and the telephoto objective optical system, which causes
problems that the wide angle image and the telephoto image cannot
be simultaneously imaged and that necessity of a mechanism for the
movable reflective member results in size increase of the
device.
[0011] In the image pickup device disclosed in PTL 3, it is
possible that the subject light beams passing through different
regions on the imaging lens are subjected to pupil separation to
simultaneously capture plural images corresponding to the subject
light beams having been subjected to the pupil separation by one
image pickup element, but no concrete configuration for
successfully capturing the wide angle image and the telephoto image
is described in PTL 3.
[0012] The present invention has been made in consideration of such
a circumstance, and has an object to provide an image pickup device
which is capable of simultaneously acquiring a first image and a
second image formed into images respectively by a central optical
system and a circular optical system that share an optical axis,
and is compact and inexpensive.
[0013] In order to achieve the above object, an image pickup device
according to an aspect of the invention includes a photographing
optical system having a central optical system disposed at a
central region and a circular optical system disposed at an outer
portion of the central optical system which are arranged along the
same optical axis, a directional sensor having plural pixels
including two-dimensionally arranged photoelectric conversion
elements, the directional sensor including plural pixels for
selectively receiving light beams of light fluxes which are
incident via the central optical system and the circular optical
system by applying pupil division, an image readout device that
acquires from the directional sensor each of an image signal
representing a first image received via the central optical system
and an image signal representing a second image received via the
circular optical system.
[0014] According to an aspect of the invention, combination of the
photographing optical system having the central optical system and
the circular optical system that share the optical axis, and the
directional sensor including plural pixels for selectively
receiving light beams of light fluxes which are incident via the
central optical system and the circular optical system by applying
pupil division allows the first image and the second image to be
simultaneously acquired by one directional sensor. The central
optical system and the circular optical system can improve quality
of an image as compared with parallel type optical systems arranged
with the optical axis being interposed therebetween.
[0015] In the image pickup device according to another aspect of
the invention, it is preferable that the directional sensor having
directional characteristics depending on pupil shapes of the
central optical system and the circular optical system at an image
surface position is used. This is because the pupil shapes of the
central optical system and the circular optical system vary
depending on the image surface position.
[0016] In the image pickup device according to still another aspect
of the invention, it is preferable that the directional sensor has
plural microlenses serving as a pupil division device, and the
number and/or positions of pixels allocated to one microlens of the
plural microlenses is the number and/or positions depending on
pupil positions and shapes of the central optical system and the
circular optical system. Specifically, variation of the pupil
shapes of the central optical system and the circular optical
system depending on the image surface position is coped with by
optimizing the number and/or position of pixels allocated to one
microlens.
[0017] In the image pickup device according to still another aspect
of the invention, it is preferable that the directional sensor has
a microlens serving as a pupil division device, the microlens
dividing a pupil image and each divided pupil image entering the
pixel, and the number of the pixels allocated to one microlens
decreases as an image height increases. If the number of the pixels
per one microlens is fixed, pupil separation is performed to allow
the light to be incident on each pixel at the central region, but,
at the outer portion (at a position of higher image height), the
pixel is brought about where the light is unlikely to be incident
or no light is incident (useless pixel). According to still another
aspect of the invention, the number of the pixels allocated to one
microlens decreases as the image height increases, which allows the
light to be incident on the all pixels and the pixels in the
directional sensor to be effectively used.
[0018] In the image pickup device according to still another aspect
of the invention, it is preferable that a size of each pixel in the
directional sensor is identical, and a size of the microlens used
decreases as the image height increases. In other words, as the
image height increases, the size of the microlens decreases, which
decreases the number of the pixels per one microlens as the image
height increases.
[0019] In the image pickup device according to still another aspect
of the invention, it is preferable that a size of the microlens is
identical, and a size of the pixel in the directional sensor
increases as the image height increases. In other words, as the
image height increases, the size of the pixel increases, which
decreases the number of the pixels per one microlens as the image
height increases.
[0020] In the image pickup device according to still another aspect
of the invention, it is preferable that the central optical system
has larger image forming magnification at the central region and
smaller image forming magnification at a periphery side. In other
words, the central optical system is made to have characteristics
like a fisheye lens. By doing so, at a (central) region where
sampling by the directional sensor becomes coarse due to the
division of the first and second images, the image forming
magnification of the central optical system is increased (image is
enlarged) to make a resultant sampling density of an object space
close to be uniform, improving quality of an image.
[0021] In the image pickup device according to still another aspect
of the invention, it is preferable that the circular optical system
has larger image forming magnification on an inner diameter side
and smaller image forming magnification on an outer diameter
side.
[0022] In the image pickup device according to still another aspect
of the invention, it is preferable that the directional sensor has
a light shielding mask serving as a pupil division device, and the
light shielding mask having an opening shape depending on pupil
shapes of the central optical system and the circular optical
system at an image surface position is used.
[0023] In the image pickup device according to still another aspect
of the invention, it is preferable that a first image circle for
the central optical system is different from a second image circle
for the circular optical system, and the directional sensor has the
pixel for selectively receiving the light by applying the pupil
division disposed at only a region where the first image circle and
the second image circle overlap one another. This allows the pixels
in the directional sensor to be effectively used.
[0024] In the image pickup device according to still another aspect
of the invention, it is preferable that the central optical system
has wider angle as compared with the circular optical system.
[0025] In the image pickup device according to still another aspect
of the invention, it is preferable that the circular optical system
has a catoptric system for reflecting the light flux two or more
times. This allows a length of the circular optical system in an
optical axis direction to be shortened, making the device
compact.
[0026] In the image pickup device according to still another aspect
of the invention, it is preferable that the directional sensor is
positioned on an object side with respect to the catoptric system
which first reflects the light flux. This makes it possible to
arrange the directional sensor on an inner side of the
photographing optical system, allowing a length of the device in
the optical axis direction to be shortened.
[0027] In the image pickup device according to still another aspect
of the invention, it is preferable that the central optical system
and the circular optical system share a part of the optical system.
This can make the device compact and reduce the cost.
[0028] The image pickup device according to still another aspect of
the invention includes a mode switcher that switches between a
first imaging mode and a second imaging mode different in a focal
length from each other, in which the image readout device acquires
from the directional sensor the image signal representing the first
image obtained by receiving the light via the central optical
system when the mode switcher switches to the first imaging mode,
and acquires from the directional sensor the image signal
representing the second image obtained by receiving the light via
the circular optical system when the mode switcher switches to the
second imaging mode. This makes it possible to selectively acquire
the first image or the second image without mechanically
switching.
[0029] In the image pickup device according to still another aspect
of the invention, the mode switcher has a switching function to
switch to a hybrid imaging mode for performing two kinds of imaging
different in the focal length, and the image readout device
simultaneously acquires from the directional sensor the image
signal representing the first image obtained by receiving the light
via the central optical system and the image signal representing
the second image obtained by receiving the light via the circular
optical system when the mode switcher switches to the hybrid
imaging mode. This allows the first image and the second image to
be simultaneously acquired.
[0030] According to the invention, combination of the photographing
optical system having the central optical system and the circular
optical system that share the optical axis, and the directional
sensor makes is possible to simultaneously acquire the first image
and the second image which are formed on an image formed surface of
the directional sensor respectively via the central optical system
and the circular optical system and by applying the pupil division.
The optical system is not required to be mechanically switched when
the first image and the second image are acquired, and the first
image and the second image can be simultaneously acquired by one
directional sensor, making the device compact and inexpensive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is an appearance perspective view of an image pickup
device according a first embodiment of the invention.
[0032] FIG. 2 is a block diagram showing an embodiment of an
internal configuration of the image pickup device shown in FIG.
1.
[0033] FIG. 3 is a sectional view showing the first embodiment of a
photographing optical system applied to the image pickup device
shown in FIG. 1.
[0034] FIG. 4 is a sectional view showing a central optical system
in the photographing optical system shown in FIG. 3.
[0035] FIG. 5 is a sectional view showing a circular optical system
in the photographing optical system shown in FIG. 3.
[0036] (a) portion and (b) portion of FIG. 6 are schematic views
showing a pupil image separation method and a light shielding mask
method, respectively.
[0037] FIG. 7 is a main part plan view of a directional sensor of
pupil image separation method.
[0038] FIG. 8 is a main part plan view of a directional sensor of
light shielding mask method.
[0039] FIG. 9 is an illustration showing pupil shapes corresponding
to the central optical system and the circular optical system, and
showing tracking of light rays by incident direction of the light
ray passing through the central optical system and the circular
optical system.
[0040] FIG. 10 is an illustration used for explaining optimization
of the directional sensor of pupil image separation method.
[0041] FIG. 11 is a main part sectional view of the optimized
directional sensor of pupil image separation method.
[0042] FIG. 12 is an illustration used for explaining optimization
of the directional sensor of light shielding mask method.
[0043] FIG. 13 is a main part sectional view of the optimized
directional sensor of light shielding mask method.
[0044] FIG. 14 is an illustration showing preferable image forming
characteristics of the central optical system.
[0045] FIG. 15 is a sectional view showing a second embodiment of a
photographing optical system.
[0046] FIG. 16 is a sectional view showing a central optical system
in the photographing optical system shown in FIG. 15.
[0047] FIG. 17 is a sectional view showing a circular optical
system in the photographing optical system shown in FIG. 15.
[0048] FIG. 18 is a sectional view showing a third embodiment of a
photographing optical system.
[0049] FIG. 19 is an appearance diagram of a smart phone as another
embodiment of an image pickup device.
[0050] FIG. 20 is a block diagram showing a main part configuration
of the smart phone.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0051] Hereinafter, a description is given of embodiments of an
image pickup device according the invention with reference to the
accompanying drawings.
<Appearance of Image Pickup Device>
[0052] FIG. 1 is an appearance perspective view of an image pickup
device of a first embodiment according to the invention. As shown
in FIG. 1, an image pickup device 10 has a photographing optical
system 12, flash emitting part 20 and the like arranged on a front
side thereof, and a shutter button 38-1 provided on a top side
thereof. A reference sign L1 designates an optical axis of the
photographing optical system 12.
[0053] FIG. 2 is a block diagram showing an internal configuration
of the image pickup device 10.
[0054] The image pickup device 10 which records captured image in a
memory card 54 is mainly characterized by the photographing optical
system 12 and directional sensor 16.
[Photographing Optical System]
[0055] FIG. 3 is a sectional view showing the first embodiment of
the photographing optical system 12 applied to the image pickup
device 10. FIG. 4 and FIG. 5 are illustrations showing in a
separated state of a central optical system 13 and a circular
optical system 14 in the photographing optical system 12.
[0056] The photographing optical system 12 includes the central
optical system 13 at a central region thereof and the circular
optical system 14 at an outer portion of the system 13 which are
arranged along the same optical axis (see FIG. 4 and FIG. 5).
[0057] The central optical system 13 is a wide angle lens
constituted by a first lens 13a, second lens 13b, third lens 13c,
lens 15a, and cover glass 15b. The cover glass 15b is disposed in
front of the directional sensor 16.
[0058] The circular optical system 14 is a telephoto lens
constituted by a first lens 14a, first reflective mirror 14b,
second reflective mirror 14c, second lens 14d, lens 15a, and cover
glass 15b. A light flux incident on the first lens 14a is reflected
twice by the first reflective mirror 14b and the second reflective
mirror 14c, and then, passes through the second lens 14d, the lens
15a, and cover glass 15b. Folding back the light flux by the first
reflective mirror 14b and the second reflective mirror 14c allows a
length of the telephoto lens having a long focal length to be
shortened in an optical axis direction.
[0059] Here, the lens 15a and the cover glass 15b are included in
an optical system shared by both central optical system 13 and
circular optical system 14.
[0060] FIG. 4 is a sectional view showing only the central optical
system 13 in the photographing optical system 12 shown in FIG.
3.
[0061] A numerical value example of the central optical system 13
including the first lens 13a, the second lens 13b, the third lens
13c, lens 15a, the cover glass 15b and the like as shown in FIG. 4
is as below [Table 1]. In FIG. 4, a surface is designated by a
surface number of a reference sign Si (i=1 to 12).
<Numerical Value Example in First Embodiment (Central Optical
System 13: Wide Angle Lens)>
TABLE-US-00001 [0062] TABLE 1 GENERAL LENS DATA Surfaces 12 Stop 2
System Aperture Image Space F# = 2.4 Glass Catalogs SCHOTT Ray
Aiming Off Apodization Uniform, Factor = 0.00000E+000 Temperature
(C.) 2.00000E+001 Pressure (ATM) 1.00000E+000 Adjust Index Data to
Environment Off Effective Focal Length 5.094742 (in air at system
temperature and pressure) Effective Focal Length 5.094742 (in image
space) Back Focal Length 0.05198607 Total Track 8.00749 in image
space F# 2.4 Paraxial Working F# 2.4 Working F# 2.332479 in image
space NA 0.2039543 Object Space NA 1.061405e-010 Stop Radius
1.061405 Paraxial Image Height 2.595901 Paraxial Magnification 0
Entrance Pupil Diameter 2.122809 Entrance Pupil Position 0.2 Exit
Pupil Diameter 2.035911 Exit Pupil Position -4.834201 Field Type
Angle (in degrees) Maximum Radial Field 27 Primary Wavelength 0.55
.mu.m Lens Units Millimeters Angular Magnification 1.042683 Fields
3 Field Type Angle (in degrees) # X Value Y Value Weight 1 0.000000
0.000000 1.000000 2 0.000000 10.000000 1.000000 3 0.000000
27.000000 1.000000 Vignetting Factors # VDX VDY VCX VCY VAN 1
0.000000 0.000000 0.000000 0.000000 0.000000 2 0.000000 0.000000
0.000000 0.000000 0.000000 3 0.000000 0.000000 0.000000 0.000000
0.000000 Wavelengths 1 Units .mu.m # Value Weight 1 0.550000
1.000000 SURFACE DATA SUMMARY: Curvature Surface Type Radius
Thickness Glass Diameter Conic Object STANDARD Infinity Infinity 0
0 Z 1 STANDARD Infinity 0.2 2.326619 0 Stop STANDARD Infinity 0.73
2.122809 0 3 STANDARD 3.641741 1.34 1.696800, 55.460000 3.258933 0
L1 4 STANDARD -2.680156 0.16 3.157928 0 5 EVENASPH -1.853771 0.6
1.583000, 30.050000 3.107938 -1.01357 L2 6 STANDARD 9.334449 0.6
3.194404 0 7 STANDARD -4.516733 0.81 1.583000, 30.050000 3.244493 0
L3 8 EVENASPH -2.167203 1.3 3.54953 -3.68581 9 STANDARD 8.777 1.21
1.583000, 30.050000 6 0 L4 10 EVENASPH 3.135 0.5574901 6 -20.3353
11 STANDARD Infinity 0.5 1.516800, 64.200000 5.2 0 Glass 12
STANDARD Infinity 5.2 0 Image SURFACE DATA DETAIL: Surface Object
STANDARD Z Surface 1 STANDARD Surface Stop STANDARD Surface 3
STANDARD L1 Surface 4 STANDARD Surface 5 EVENASPH L2 Coefficient on
r2 0 Coefficient on r4 0.00250152 Coefficient on r6 -0.000193495
Coefficient on r8 0 Coefficient on r10 0 Coefficient on r12 0
Coefficient on r14 0 Coefficient on r16 0 Surface 6 STANDARD
Surface 7 STANDARD L3 Surface 8 EVENASPH Coefficient on r2 0
Coefficient on r4 -0.00387959 Coefficient on r6 0.00277573
Coefficient on r8 0.000133673 Coefficient on r10 3.64299e-005
Coefficient on r12 0 Coefficient on r14 0 Coefficient on r16 0
Surface 9 STANDARD L4 Aperture Floating Aperture Maximum Radius 3
Surface 10 EVENASPH Coefficient on r2 0 Coefficient on r4
-0.0137242 Coefficient on r6 0.00142977 Coefficient on r8
-0.000101171 Coefficient on r10 1.64597e-006 Coefficient on r12 0
Coefficient on r14 0 Coefficient on r16 0 Aperture Floating
Aperture Maximum Radius 3 Surface 11 STANDARD Glass Aperture
Floating Aperture Maximum Radius 2.6 Surface 12 Image STANDARD
[0063] FIG. 5 is a sectional view showing only the circular optical
system 14 in the photographing optical system 12 shown in FIG.
3.
[0064] As shown in FIG. 5, a numerical value example of the
circular optical system 14 including the first lens 14a, the first
reflective mirror 14b, the second reflective mirror 14c, the second
lens 14d, the lens 15a, the cover glass 15b and the like is as
below [Table 2]. In FIG. 5, a surface is designated by a surface
number of a reference sign Si (i=1 to 17).
<Numerical Value Example in First Embodiment (Circular Optical
System 14: Telephoto Lens)>
TABLE-US-00002 [0065] TABLE 2 GENERAL LENS DATA Surfaces 17 Stop 2
System Aperture Entrance Pupil Diameter = 16 Glass Catalogs SCHOTT
Ray Aiming Off Apodization Uniform, Factor = 0.00000E+000
Temperature (C.) 2.00000E+001 Pressure (ATM) 1.00000E+000 Adjust
Index Data to Environment Off Effective Focal Length 13.08991(in
air at system temperature and pressure) Effective Focal Length
13.08991 (in image space) Back Focal Length -0.01287807 Total Track
10.8 in image space F# 0.8181191 Paraxial Working F# 0.8181191
Working F# 0.8026466 in image space NA 0.5214791 Object Space NA
8e-010 Stop Radius 8 Paraxial Image Height 1.839666 Paraxial
Magnification 0 Entrance Pupil Diameter 16 Entrance Pupil Position
8 Exit Pupil Diameter 13.98026 Exit Pupil Position -11.4504 Field
Type Angle (in degrees) Maximum Radial Field 8 Primary Wavelength
0.5875618 .mu.m Lens Units Millimeters Angular Magnification
1.144481 Fields 8 Field Type Angle (in degrees) # X Value Y Value
Weight 1 0.000000 0.000000 1.000000 2 0.000000 2.000000 1.000000 3
0.000000 4.000000 1.000000 4 0.000000 6.000000 0.000000 5 0.000000
8.000000 0.000000 6 0.000000 -3.000000 1.000000 7 0.000000
-5.000000 0.000000 8 0.000000 -7.000000 0.000000 Vignetting Factors
# VDX VDY VCX VCY VAN 1 0.000000 0.000000 0.000000 0.000000
0.000000 2 0.000000 0.000000 0.000000 0.000000 0.000000 3 0.000000
0.000000 0.000000 0.000000 0.000000 4 0.000000 0.000000 0.000000
0.000000 0.000000 5 0.000000 0.000000 0.000000 0.000000 0.000000 6
0.000000 0.000000 0.000000 0.000000 0.000000 7 0.000000 0.000000
0.000000 0.000000 0.000000 8 0.000000 0.000000 0.000000 0.000000
0.000000 Wavelengths 3 Units .mu.m # Value Weight 1 0.486133
1.000000 2 0.587562 1.000000 3 0.656273 1.000000 SURFACE DATA
SUMMARY: Curvature Surfaces Type Radius Thickness Glass Diameter
Conic Object STANDARD Infinity Infinity 0 0 1 STANDARD Infinity 8
18.24865 0 Stop STANDARD Infinity 0 16 0 3 EVENASPH -38.9422 1.2
SK6 16.24017 -0.8764911 4 EVENASPH -189.0192 1.6 16.38624 28.84007
5 STANDARD -28.87438 0 MIRROR 16.66602 -0.6495759 6 STANDARD
Infinity -1.6 17.69315 0 7 EVENASPH -189.0192 -1.2 SK6 16.30225
28.84007 8 EVENASPH -38.9422 -7 15.5352 -0.8764911 9 STANDARD 110
4.1 MIRROR 12.98573 246.4822 10 STANDARD Infinity 0 8.541992 0 11
EVENASPH 10.48836 0.81 1.583000, 30.05000 7.221966 0.1581105 L3 12
EVENASPH -39.02395 0 7.03354 -1544.723 13 STANDARD Infinity 1.8
7.700362 0 14 STANDARD 8.777 1.21 1.583000, 30.05000 6 0 L4 15
EVENASPH 3.135 0.5574901 5.2 -20.3353 16 STANDARD Infinity 0.5
1.516800, 64.20000 2.739079 0 Glass 17 Image STANDARD Infinity 5.2
0 SURFACE DATA DETAIL: Surface Object STANDARD Surface 1 STANDARD
Aperture Circular Aperture Minimum Radius 6 Maximum Radius 10
Surface Stop STANDARD Aperture Circular Aperture Minimum Radius 5
Maximum Radius 9 Surface 3 EVENASPH Coefficient on r2 0 Coefficient
on r4 1.8366007e-007 Coefficient on r6 -2.6273128e-008 Coefficient
on r8 0 Coefficient on r10 0 Coefficient on r12 0 Coefficient on
r14 0 Coefficient on r16 0 Aperture Circular Aperture Minimum
Radius 4 Maximum Radius 9 Surface 4 EVENASPH Coefficient on r2 0
Coefficient on r4 -4.922135e-007 Coefficient on r6 7.1974477e-008
Coefficient on r8 0 Coefficient on r10 0 Coefficient on r12 0
Coefficient on r14 0 Coefficient on r16 0 Aperture Circular
Aperture Minimum Radius 4 Maximum Radius 9 Surface 5 STANDARD
Mirror Substrate Curved, Thickness = 3.33320E-001 Aperture Circular
Aperture Minimum Radius 4 Maximum Radius 9 Surface 6 STANDARD
Surface 7 EVENASPH Coefficient on r2 0 Coefficient on r4
-4.922135e-007 Coefficient on r6 7.1974477e-008 Coefficient on r8 0
Coefficient on r10 0 Coefficient on r12 0 Coefficient on r14 0
Coefficient on r16 0 Aperture Circular Aperture Minimum Radius 4
Maximum Radius 9 Surface 8 EVENASPH Coefficient on r2 0 Coefficient
on r4 1.8366007e-007 Coefficient on r6 -2.6273128e-008 Coefficient
on r8 0 Coefficient on r10 0 Coefficient on r12 0 Coefficient on
r14 0 Coefficient on r16 0 Aperture Circular Aperture Minimum
Radius 4 Maximum Radius 9 Surface 9 STANDARD Mirror Substrate
Curved, Thickness = 2.59715E-001 Aperture Circular Aperture Minimum
Radius 3.5 Maximum Radius 6 Surface 10 STANDARD Aperture Circular
Aperture Minimum Radius 1.622247 Maximum Radius 6 Surface 11
EVENASPH L3 Coefficient on r2 0 Coefficient on r4 -0.00078081372
Coefficient on r6 0.00010352365 Coefficient on r8 8.2555892e-006
Coefficient on r10 4.6862634e-007 Coefficient on r12 0 Coefficient
on r14 0 Coefficient on r16 0 Aperture Circular Aperture Minimum
Radius 1.774765 Maximum Radius 3.6 Surface 12 EVENASPH Coefficient
on r2 0 Coefficient on r4 -0.0012390633 Coefficient on r6
0.00034352026 Coefficient on r8 -4.5651306e-006 Coefficient on r10
5.9463077e-007 Coefficient on r12 0 Coefficient on r14 0
Coefficient on r16 0 Aperture Circular Aperture Minimum Radius
1.774765 Maximum Radius 3.6 Aperture Circular Aperture Minimum
Radius 1.622247 Maximum Radius 3.8 Surface 14 STANDARD Aperture
Floating Aperture Maximum Radius 3 Surface 15 EVENASPH Coefficient
on r2 0 Coefficient on r4 -0.0137242 Coefficient on r6 0.00142977
Coefficient on r8 -0.000101171 Coefficient on r10 1.64597e-006
Coefficient on r12 0 Coefficient on r14 0 Coefficient on r16 0
Aperture Floating Aperture Maximum Radius 2.6 Surface 16 STANDARD
Glass Surface 17 Image STANDARD
[Directional Sensor]
[0066] Next, a description is given of the directional sensor 16
shown in FIG. 2.
[0067] The directional sensor 16 has a plurality of pixels
including two-dimensionally arranged photoelectric conversion
elements (light receiving cells), and is configured to include
pixels for selectively receiving the light beams of the light
fluxes which are incident via the central optical system 13 and the
circular optical system 14 by applying pupil division by a pupil
division device shown below.
[0068] The directional sensor is classified into a pupil image
separation method using a pupil imaging lens (microlens) and a
light shielding mask method.
[0069] (a) portion of FIG. 6 is a schematic view showing the pupil
image separation method. In the pupil image separation method, the
plural light receiving cells 18 (pixels) are allocated to one
microlens 17a, and a pupil image entering into the microlens 17a is
formed into an image on the plural light receiving cells 18 by the
microlens 17a. Therefore, the pupil image is separated depending on
an angle of the light incident on the microlens 17a to be formed
into an image on the corresponding light receiving cell 18.
[0070] (b) portion of FIG. 6 is a schematic view showing the light
shielding mask method. In the light shielding mask method, a light
shielding mask 19 is disposed between the microlens 17b and the
light receiving cell 18, and the light shielding mask 19 blocks out
a light incident in a direction of a part of the light beams
incident on the microlens 17b and makes a light only in the
incident direction corresponding to an opening of the light
shielding mask 19 to be incident on the light receiving cell
18.
[0071] FIG. 7 is a main part plan view of a directional sensor of
pupil image separation method. This directional sensor is a four
pixels one microlens type for sharing one microlens 17a by four
pixels, and can acquire images of four viewpoints of left, right,
top and bottom. Four pixels corresponding to each microlens 17a
respectively have any one color filter of red (R), green (G) and
blue (B) color filters arranged. In this case, the images of four
viewpoints are rotated by 45 degrees to respectively obtain a
filter arrangement of Bayer arrangement.
[0072] The number of pixels allocated to one microlens is
arbitrary, and, for example, 100 pixels may be allocated to one
microlens in a certain case. In this case, a pixel size per one
viewpoint is decreased.
[0073] FIG. 8 is a main part plan view of a directional sensor of
light shielding mask method. This directional sensor has pairs of
pixels for each color of RGB arranged thereon, one of the pair
having a light shielding mask 19a disposed whose opening
(rectangular part) is formed on the left side on FIG. 8, and the
other of the pair having a light shielding mask 19b disposed whose
opening is formed on the right side. Images including pixels of odd
lines and pixels of even lines read out from the directional sensor
correspond to images of two viewpoints in left-and-right direction.
Each image is a mosaic image of the Bayer arrangement.
[0074] The opening of the light shielding mask may have any shape,
and the light only in the incident direction corresponding to the
opening can be made incident on the light receiving cell.
[0075] FIG. 9 is an illustration showing pupil shapes corresponding
to the central optical system 13 and the circular optical system
14, and showing tracking of light rays by incident direction of the
light ray passing through the central optical system 13 and the
circular optical system 14.
[0076] (a) portion of FIG. 9 shows an illustration tracking an
incident light at an incident angle of 0 degree, and the pupil
shapes corresponding to the central optical system 13 and the
circular optical system 14. As shown in the figure, in a layout
where the central optical system 13 is embedded at a central region
of the circular optical system 14 of reflective mirror type, an
incident light straight from the front results in a circular pupil
and a toric pupil.
[0077] (b) portion of FIG. 9 shows an illustration tracking an
incident light at an incident angle of 3.2 degree, and the pupil
shapes corresponding to the central optical system 13 and the
circular optical system 14, and (c) portion of FIG. 9 shows an
illustration tracking an incident light at an incident angle of
14.4 degree, and the pupil shapes corresponding to the central
optical system 13 and the circular optical system 14.
[0078] As shown in (b) portion and (c) portion of FIG. 9, as an
angle of oblique incident increases, mechanical vignetting begins
to occur in the circular optical system 14 that is a telephoto lens
having a narrow field and the toric pupil is decreased and deformed
into a crescentic shape, and when the angle reaches 14.4 degrees,
the light rarely passes through the pupil.
[0079] The circular pupils corresponding to the central optical
system 13 are shown with the same shape on FIG. 9, but are deformed
depending on the incident angle.
[Optimization of Directional Sensor Configuration]
[0080] As described in FIG. 9, the pupil shape/size for effectively
passing the light varies depending on the incident angle (depending
on an image height on the sensor surface).
[0081] Therefore, in the case of the directional sensor of pupil
image separation method shown in FIG. 10, if a configuration of the
directional sensor of pupil image separation method is uniform
between the center and periphery of the sensor, the useless light
receiving cell where no light is incident is brought about at the
periphery of the sensor, which reduces light use efficiency.
[0082] FIG. 11 is an illustration showing the first embodiment of a
directional sensor 16a according to the invention. The directional
sensor 16a has a configuration in which the number of the light
receiving cells covered by one microlens decreases from the center
toward the periphery (as the image height increases). In the
example shown in FIG. 11, the number of the light receiving cells
covered by one microlens (the number of cells in an up-and-down
direction on the plane of paper) is three at the center (incident
angle 0 degree), two at a halfway portion (incident angle 3.2
degrees), and one at the periphery (incident angle 14.4
degrees).
[0083] As shown in FIG. 11, in a case where a size of the light
receiving cell is identical, a size and focal length of the
microlens used is smaller and shorter toward the periphery. This
allows that the closer to the periphery, the higher density
sampling is obtained.
[0084] In the periphery of the directional sensor, the microlens
corresponds to the light receiving cell on a one-to-one basis, and
the pupil division function is not possessed. Specifically, an
image circle corresponding to the circular optical system 14 is
virtually smaller than an image circle corresponding to the central
optical system 13 due to the mechanical vignetting in the sensor
periphery. Therefore, in the directional sensor 16a, a pixel having
the pupil division function is disposed at only a region where two
image circles overlap one another, and a pixel not having the pupil
division function is disposed at a region where the image circles
do not overlap one another.
[0085] Note that it may be that the size of the microlens is
uniform and the size of the light receiving cell increases toward
the periphery. In this case, the closer the periphery, the larger a
light receiving area of the light receiving cell, which leads to an
advantageous S/N (signal-to-noise ratio).
[0086] On the other hand, in a case of the directional sensor of
light shielding mask method shown in FIG. 12, if the shape of the
light shielding mask is uniform between the center and periphery of
the sensor, the useless light receiving cell where no light is
incident is brought about at the periphery of the sensor, which
reduces light use efficiency.
[0087] FIG. 13 is an illustration showing a second embodiment of a
directional sensor 16b according to the invention. The directional
sensor 16b employs the light shielding mask which has an opening of
a shape/size corresponding to the pupil shape, the pupil shapes of
the central optical system 13 and circular optical system 14
varying depending on a position of the sensor surface.
[0088] In other words, the light shielding mask having a circle or
toric opening is used at the sensor center, and the toric pupil is
gradually decreased and deformed into a crescentic shape toward the
periphery, and thus, the opening shape of the mask is made to have
the similar shape. In addition to this, it is preferable to
slightly shift the optical axis of the micro (condenser) lens with
respect to the light receiving cell (to perform scaling). It may be
that, at a region in the periphery where the toric pupil is fully
mechanically vignetted, no light receiving cell for the circular
optical system 14 is arranged and only the light receiving cell for
the central optical system 13 is arranged. In this case, an
incident light amount can be increased in the sensor periphery
without necessity of disposing the light shielding mask on the
light receiving cell for the central optical system 13 in the
sensor periphery.
[New Problem of Directional Sensor 16a]
[0089] In the directional sensor 16a in the first embodiment shown
in FIG. 11, the closer to the sensor periphery, the higher density
sampling can be obtained as described above. This raises, when
viewed from the opposite side, a problem of lower density sampling
at the center.
[0090] Then, this problem is dealt with on the photographing
optical system side. Specifically, used is an optical system having
image forming characteristics that a magnifying power (image
forming magnification) for an object space is different between the
center and the periphery. In other words, the central optical
system 13 uses an optical system having the image forming
characteristics that the image forming magnification is large at
the central region and small on the peripheral side, like a fisheye
lens shown in FIG. 14. This finally uniforms the sampling density
in the object space.
[0091] On the other hand, in the directional sensor 16a in the
first embodiment, the closer to the sensor center, the higher
density sampling can be obtained for the images corresponding to
the circular optical system 14.
[0092] Therefore, the circular optical system 14 uses an optical
system having the image forming characteristics that the image
forming magnification is smaller on the inner diameter side and
larger on the outer diameter side (characteristics similar to a
reverse fisheye lens). This can uniform the sampling density in the
object space.
[0093] Referring back to FIG. 2, the image pickup device 10
includes the photographing optical system 12 having the central
optical system 13 and circular optical system 14 described in FIG.
3 to FIG. 5, and the directional sensor 16 that is any one of the
directional sensor 16a in the first embodiment described in FIG. 11
or the directional sensor 16b in the second embodiment described in
FIG. 13. Operation of the overall device is collectively controlled
by a central processing unit (CPU) 40.
[0094] The image pickup device 10 is provided with an operation
unit 38 including a shutter button 38-1, mode dial (mode switcher),
play button, MENU/OK key, cross-shaped key, BACK key and the like.
The signal from the operation unit 38 is input to the CPU 40, and
the CPU 40 controls the circuits in the image pickup device 10 on
the basis of the input signal to perform, for example, imaging
operation control, image processing control, image data record/play
control, display control of a liquid crystal monitor (LCD) 30, and
the like.
[0095] The shutter button 38-1 (FIG. 1) which is an operation
button for inputting an instruction to start imaging includes a
two-stage stroke type switch having an S1 switch to be turned on in
halfway press and an S2 switch to be turned on in full press.
[0096] The mode dial is a selection device for switching among an
automatic imaging mode for imaging a still image, a manual imaging
mode, a scene position for human, landscape, nightscape or the
like, and a moving picture mode for taking a moving picture. The
mode dial functions in the imaging mode as a selection device for
switching among a first imaging mode for acquiring a first image
(wide angle image) formed via the central optical system 13, a
second imaging mode for acquiring a second image (telephoto image)
formed via the circular optical system 14, a hybrid imaging mode
for simultaneously acquiring the wide angle image and the telephoto
image, and the like.
[0097] The play button is a button for switching to a play mode for
displaying the imaged and recorded still image or moving picture on
the liquid crystal monitor 30. The MENU/OK key is an operation key
having both a function as a menu button for instructing to display
a menu on the liquid crystal monitor 30 screen and a function as an
OK button for instructing to confirm and execute the selected
content. The cross-shaped key is an operation unit for inputting an
instruction of four directions up, down, right and left, and
functions as a button for selecting an item from a menu screen and
instructing to select various setting items from each menu (cursor
movement control device). Up/down keys of the cross-shaped key
function as a zoom switch in imaging or a play zoom switch in the
play mode, and right/left keys function as a frame-by-frame
playback (forward/backward playback) button for in the play mode.
The BACK key is used to delete a desired target such as the
selected item, cancel the instructed content, or undo the last
operation.
[0098] In the imaging mode, the subject light is formed into an
image on a light receiving surface of the directional sensor 16 via
the photographing optical system 12.
[0099] A subject image formed on the light receiving surface of
each light receiving cell of the directional sensor 16 is converted
into a signal voltage (or electrical charge) of an amount
corresponding to the incident light amount thereof. The directional
sensor 16 has a color filter of RGB for each microlens disposed
thereon.
[0100] The signal voltage (or electrical charge) accumulated in the
directional sensor 16 is stored in the light receiving cell itself
or a capacitor attached. The accumulated signal voltage (or
electrical charge) is read out by way of a method of MOS type image
pickup element using the X-Y address method (so-called CMOS sensor)
by a sensor control unit 32 (image readout device) when selecting
the pixel position.
[0101] This makes it possible to read out from the directional
sensor 16 image signals representing the wide angle image (first
image) constituted by a pixel group corresponding to the central
optical system 13 and image signals representing the telephoto
image (the second image) constituted by a pixel group corresponding
to the circular optical system 14.
[0102] The image signal (voltage signal) read out from the
directional sensor 16 is subjected to a correlated double sampling
process (a process in which, for the purpose of reducing noises
(especially, thermal noise) and the like contained in a sensor
output signal, a difference between a feed-through component level
and an image signal component level contained in an output signal
for one pixel of the sensor is taken to obtain the accurate pixel
data) such that the R, G, or B signal for each pixel is sampled and
held, and then, after being amplified, added to an A/D converter
21. The A/D converter 21 converts the serially input R, G, and B
signals into digital R, G, and B signals and outputs to an image
input controller 22. Some MOS type sensors have the A/D converter
built therein, and in this case, the R, G, and B digital signals
are directly output from the directional sensor 16.
[0103] The image signals representing the wide angle image and the
image signals representing the telephoto image can be selectively
read out by selecting the pixel position and reading out the pixel
data of the directional sensor 16, but it may be that all image
data is read out from the directional sensor 16 and temporarily
stored in a memory (SDRAM) 48, and then, two images data of the
wide angle image and the telephoto image is extracted from the
memory 48.
[0104] A digital signal processor 24 subjects the digital image
signal input via the image input controller 22 to a predetermined
signal process such as a offset process, gain control processing
including white balance correction and sensitivity correction,
gamma correction processing, RGB/YC conversion processing for
converting from the RGB signals to a luminance signal Y and
color-difference signals Cr and Cb.
[0105] The image data processed by an image processor 25 is input
to a VRAM (Video Random Access Memory) 50. The image data read out
from the VRAM 50 is encoded by a video encoder 28, and output to
the liquid crystal monitor 30 provided on the back side of a
camera, which allows the subject image to be displayed on a display
screen of the liquid crystal monitor 30.
[0106] When the shutter button 38-1 of the operation unit 38 is
pressed down at the first stage (halfway press), the CPU 40 starts
an AE operation, and the image data output from the A/D converter
21 is taken in an AE detection unit 44.
[0107] The AE detection unit 44 cumulates G signals in the entire
screen or cumulates the G signals weighted differently between the
central region and outer portion in the screen to output that
cumulated value to the CPU 40. The CPU 40 calculates brightness of
the subject (imaging Ev value) on the basis of the cumulated value
input from the AE detection unit 44, determines based on the
imaging Ev value an aperture value of a diaphragm (not shown) and
an electronic shutter (shutter speed) of the directional sensor 16
in accordance with a predetermined program diagram, and controls
based on the determined aperture value the diaphragm as well as
controls based on the determined the shutter speed an electrical
charge accumulation duration in the directional sensor 16 via the
sensor control unit 32.
[0108] After the AE operation ends, when the shutter button 38-1 is
pressed at the second stage (full press), the image data output
from the A/D converter 21 in response to the pressing is input to
and temporarily stored in the memory (SDRAM: Synchronous Dynamic
RAM) 48 from the image input controller 22. The image data
temporarily stored in the memory 48 is adequately read out by the
digital signal processor 24 and the image processor 25, where a
predetermined signal process including a process for generating
luminance data and color-difference data of the image data (YC
processing) is performed. The image data having being subjected to
the YC processing (YC data) is again stored in the memory 48.
[0109] The YC data stored in the memory 48 is respectively output
to a compression and decompression processor 26 and subjected to a
predetermined compression process such as the JPEG (Joint
Photographic Experts Group), and thereafter, recorded via a media
controller 52 in the memory card 54.
[0110] Then, when the first imaging mode or the second imaging mode
is selected by use of the mode dial, the wide angle image or the
telephoto image can be selectively acquired, and when the hybrid
imaging mode is selected by use of the mode dial, the wide angle
image and the telephoto image can be simultaneously acquired. This
makes it possible to acquire the wide angle image and the telephoto
image without mechanically switching between the wide angle lens
and the telephoto lens and without a zoom operation of the zoom
lens.
[Second Embodiment of Photographing Optical System]
[0111] FIG. 15 is a sectional view showing a second embodiment of a
photographing optical system 112 applied to the image pickup device
10. FIG. 16 and FIG. 17 are illustrations showing in a separated
state of a central optical system 113 and circular optical system
114 in a photographing optical system 112, respectively.
[0112] The photographing optical system 112 includes the central
optical system 113 at a central region thereof and the circular
optical system 114 at an outer portion of the system 113 which are
arranged along the same optical axis (see FIG. 16 and FIG. 17).
[0113] The central optical system 113 is a wide angle lens
constituted by a first lens 113a, second lens 113b, third lens
113c, lens 115a, and cover glass 115b. The cover glass 115b is
disposed in front of the directional sensor 16.
[0114] The circular optical system 114 is a telephoto lens
constituted by a first reflective mirror 114a, second reflective
mirror 114b, lens 114c, lens 115a, and cover glass 115b.
[0115] Here, the lens 115a and the cover glass 115b are included in
an optical system shared by both central optical system 113 and
circular optical system 114.
[0116] The photographing optical system 112 in the second
embodiment has the lenses of the circular optical system the number
of which is less by one than the photographing optical system 12 in
the first embodiment shown in FIG. 3.
[0117] The image formed position is positioned on the object side
with respect to the first reflective mirror 114a, and the
directional sensor 16 is arranged on the object side with respect
to the first reflective mirror 114a. This allows that a thickness
of an image pickup unit including the photographing optical system
112 and directional sensor 16 is a thickness of the photographing
optical system 112.
[0118] A numerical value example of the central optical system 113
including the first lens 113a, the second lens 113b, the third lens
113c, the lens 115a, the cover glass 115b and the like as shown in
FIG. 16 is as below [Table 3]. In FIG. 16, a surface is designated
by a surface number of a reference sign Si (i=1 to 12).
<Numerical Value Example in Second Embodiment (Central Optical
System 113: Wide Angle Lens)>
TABLE-US-00003 [0119] TABLE 3 GENERAL LENS DATA Surfaces 12 Stop 2
System Aperture Image Space F# = 2.8 Glass Catalogs SCHOTT Ray
Aiming Off Apodization Uniform, Factor = 0.00000E+000 Temperature
(C.) 2.00000E+001 Pressure (ATM) 1.00000E+000 Adjust Index Data to
Environment Off Effective Focal Length 4.380528 (in air at system
temperature and pressure) Effective Focal Length 4.380528 (in image
space) Back Focal Length -0.06733382 Total Track 7.03 in image
space F# 2.8 Paraxial Working F# 2.8 Working F# 2.831729 in image
space NA 0.1757906 Object Space NA 7.822371e-011 Stop Radius
0.7822371 Paraxial Image Height 2.23199 Paraxial Magnification 0
Entrance Pupil Diameter 1.564474 Entrance Pupil Position 0.5 Exit
Pupil Diameter 2.226372 Exit Pupil Position -6.301174 Field Type
Angle (in degrees) Maximum Radial Field 27 Primary Wavelength 0.55
.mu.m Lens Units Millimeters Angular Magnification 0.7027013 Fields
3 Field Type Angle (in degrees) # X Value Y Value Weight 1 0.000000
0.000000 1.000000 2 0.000000 10.000000 1.000000 3 0.000000
27.000000 1.000000 Vignetting Factors # VDX VDY VCX VCY VAN 1
0.000000 0.000000 0.000000 0.000000 0.000000 2 0.000000 0.000000
0.000000 0.000000 0.000000 3 0.000000 0.000000 0.000000 0.000000
0.000000 Wavelengths 1 Units .mu.m # Value Weight 1 0.550000
1.000000 SURFACE DATA SUMMARY: Curvature Surfaces Type Radius
Thickness Glass Diameter Conic Object STANDARD Infinity Infinity 0
0 2.8 1 STANDARD Infinity 0.5 2 0 Stop STANDARD Infinity 0 1.6 0 3
STANDARD 2.524873 1.1 1.696800, 55.460000 3 0 L1 4 STANDARD
-3.770955 0.16 3 0 5 EVENASPH -2.112843 0.35 1.583000, 30.050000 3
-1.01357 L2 6 STANDARD 2.654284 0.7 3 0 7 STANDARD -10.79486 0.81
1.583000, 30.050000 3.4 0 L3 8 EVENASPH -2.531731 0.2 3.4 -3.68581
9 STANDARD 3.901448 1.21 1.583000, 30.050000 5.2 0 L4 10 EVENASPH
5.719637 1.5 5.2 -20.3353 11 STANDARD Infinity 0.5 1.516800,
64.200000 5.2 0 Glass 12 STANDARD Infinity 5.2 0 Image SURFACE DATA
DETAIL: Surface Object STANDARD 2.8 Surface 1 STANDARD Surface Stop
STANDARD Surface 3 STANDARD L1 Aperture Floating Aperture Maximum
Radius 1.5 Surface 4 STANDARD Aperture Floating Aperture Maximum
Radius 1.5 Surface 5 EVENASPH L2 Coefficient on r2 0 Coefficient on
r4 0.00250152 Coefficient on r6 -0.000193495 Coefficient on r8 0
Coefficient on r10 0 Coefficient on r12 0 Coefficient on r14 0
Coefficient on r16 0 Aperture Floating Aperture Maximum Radius 1.5
Surface 6 STANDARD Aperture Floating Aperture Maximum Radius 1.5
Surface 7 STANDARD L3 Aperture Floating Aperture Maximum Radius 1.7
Surface 8 EVENASPH Coefficient on r2 0 Coefficient on r4
-0.00387959 Coefficient on r6 0.00277573 Coefficient on r8
0.000133673 Coefficient on r10 3.64299e-005 Coefficient on r12 0
Coefficient on r14 0 Coefficient on r16 0 Aperture Floating
Aperture Maximum Radius 1.7 Surface 9 STANDARD L4 Aperture Floating
Aperture Maximum Radius 2.6 Surface 10 EVENASPH Coefficient on r2 0
Coefficient on r4 -0.0137242 Coefficient on r6 0.00142977
Coefficient on r8 -0.000101171 Coefficient on r10 1.64597e-006
Coefficient on r12 0 Coefficient on r14 0 Coefficient on r16 0
Aperture Floating Aperture Maximum Radius 2.6 Surface 11 STANDARD
Glass Aperture Floating Aperture Maximum Radius 2.6 Surface 12
Image STANDARD
[0120] FIG. 17 is a sectional view showing only the circular
optical system 114 in the photographing optical system 112 shown in
FIG. 15.
[0121] As shown in FIG. 17, a numerical value example of the
circular optical system 114 including the first reflective mirror
114a, the second reflective mirror 114b, the lens 114c, the lens
115a, the cover glass 115b and the like is as below [Table 4]. In
FIG. 17, a surface is designated by a surface number of a reference
sign Si (I=1 to 13).
<Numerical Value Example in Second Embodiment (Circular Optical
System 114: Telephoto Lens)>
TABLE-US-00004 [0122] TABLE 4 GENERAL LENS DATA Surfaces 13 Stop 2
System Aperture Entrance Pupil Diameter = 16 Glass Catalogs SCHOTT
Ray Aiming Off Apodization Uniform, Factor = 0.00000E+000
Temperature (C.) 2.00000E+001 Pressure (ATM) 1.00000E+000 Adjust
Index Data to Environment Off Effective Focal Length 13.18049(in
air at system temperature and pressure) Effective Focal Length
13.18049(in image space) Back Focal Length 0.05954598 Total Track
10.8 in image space F# 0.8237809 Paraxial Working F# 0.8237809
Working F# 0.7994582 in image space NA 0.5188624 Object Space NA
8e-010 Stop Radius 8 Paraxial Image Height 0.9216699 Paraxial
Magnification 0 Entrance Pupil Diameter 16 Entrance Pupil Position
8 Exit Pupil Diameter 72.10137 Exit Pupil Position 59.45525 Field
Type Angle (in degrees) Maximum Radial Field 4 Primary Wavelength
0.5875618 .mu.m Lens Units Millimeters Angular Magnification
-0.221904 Fields 6 Field Type Angle (in degrees) # X Value Y Value
Weight 1 0.000000 0.000000 1.000000 2 0.000000 1.000000 1.000000 3
0.000000 2.000000 1.000000 4 0.000000 3.000000 1.000000 5 0.000000
3.000000 0.000000 6 0.000000 4.000000 01.000000 Vignetting Factors
# VDX VDY VCX VCY VAN 1 0.000000 0.000000 0.000000 0.000000
0.000000 2 0.000000 0.000000 0.000000 0.000000 0.000000 3 0.000000
0.000000 0.000000 0.000000 0.000000 4 0.000000 0.000000 0.000000
0.000000 0.000000 5 0.000000 0.000000 0.000000 0.000000 0.000000 6
0.000000 0.000000 0.000000 0.000000 0.000000 Wavelengths 3 Units
.mu.m # Value Weight 1 0.486133 1.000000 2 0.587562 1.000000 3
0.656273 1.000000 SURFACE DATA SUMMARY: Curvature Surfaces Type
Radius Thickness Glass Diameter Conic Object STANDARD Infinity
Infinity 0 0 1 STANDARD Infinity 8 17.11883 0 Stop STANDARD
Infinity 0 16 0 3 STANDARD Infinity 2.8 16 0 4 STANDARD -37.69787 0
MIRROR 16.27126 -2.783951 5 STANDARD Infinity -9.8 16.87826 0 6
STANDARD 549.2888 4.1 MIRROR 9.307526 13659.01 7 STANDARD Infinity
0 5.943563 0 8 STANDARD 24.47484 0.81 1.583000, 30.050000 6.4 0 L3
9 EVENASPH 60.56264 0.2 6.4 546.4789 10 STANDARD 3.901448 1.21
1.583000, 30.050000 5.6 0 L4 11 EVENASPH 5.719637 1.5 5.6 -20.3353
12 STANDARD Infinity 0.5 1.516800, 64.200000 5.2 0 Glass 13 Image
STANDARD Infinity 5.2 0 SURFACE DATA DETAIL: Surface Object
STANDARD Surface 1 STANDARD Aperture Circular Aperture Minimum
Radius 6 Maximum Radius 10 Surface Stop STANDARD Aperture Circular
Aperture Minimum Radius 5 Maximum Radius 9 Surface 3 STANDARD
Surface 4 STANDARD Mirror Substrate Curved, Thickness =
3.25425E-001 Aperture Circular Aperture Minimum Radius 4 Maximum
Radius 9 Surface 5 STANDARD Surface 6 STANDARD Mirror Substrate
Curved, Thickness = 1.86151E-001 Aperture Circular Aperture Minimum
Radius 3 Maximum Radius 6 Surface 7 STANDARD Aperture Circular
Aperture Minimum Radius 1.622247 Maximum Radius 6 Surface 8
STANDARD L3 Aperture Floating Aperture Maximum Radius 3.2 Surface 9
EVENASPH Coefficient on r2 0 Coefficient on r4 -0.00207824
Coefficient on r6 0.0017115516 Coefficient on r8 -0.0002973863
Coefficient on r10 2.2547512e-005 Coefficient on r12 0 Coefficient
on r14 0 Coefficient on r16 0 Aperture Floating Aperture Maximum
Radius 3.2 Surface 10 STANDARD L4 Aperture Floating Aperture
Maximum Radius 2.8 Surface 11 EVENASPH Coefficient on r2 0
Coefficient on r4 -0.0137242 Coefficient on r6 0.00142977
Coefficient on r8 -0.000101171 Coefficient on r10 1.64597e-006
Coefficient on r12 0 Coefficient on r14 0 Coefficient on r16 0
Aperture Floating Aperture Maximum Radius 2.8 Surface 12 STANDARD
Glass Aperture Floating Aperture Maximum Radius 2.6 Surface 13
Image STANDARD
[Third Embodiment of Photographing Optical System]
[0123] FIG. 18 is a sectional view showing a third embodiment of
the photographing optical system applied to the image pickup device
10.
[0124] A photographing optical system 212 includes a central
optical system 213 at a central region thereof and a circular
optical system 214 at an outer portion of the system 213 which are
arranged along the same optical axis.
[0125] The central optical system 213 is a telephoto lens
constituted by a first lens 213a, second lens 213b, and lens 215,
and has an angle of view .alpha..
[0126] The circular optical system 214 is a wide angle lens
constituted by a lens 214a and lens 215, and has an angle of view
.beta. (.beta.>.alpha.), which is a wide angle as compared with
the central optical system 213. Here, the lens 215 is included in
an optical system shared by both the central optical system 213 and
the circular optical system 214.
[0127] The photographing optical system 212 in the third
embodiment, as compared with photographing optical systems in the
first and second embodiments, is different in that the reflective
mirror is not used, and the central optical system 213 is a
telephoto lens and the circular optical system 214 is a wide angle
lens.
[0128] Examples of another embodiment of the image pickup device 10
include, for example, a mobile phone and smartphone having a camera
functionality, PDA (Personal Digital Assistants), portable game
console. Hereinafter, a description is given in detail using the
smartphone as an example with reference to the drawings.
<Configuration of Smart Phone>
[0129] FIG. 19 shows an outer appearance of a smartphone 500 as
another embodiment of the image pickup device 10. The smartphone
500 shown in FIG. 19 having a housing 502 shaped in a flat plate
includes on one face of the housing 502 a display and input unit
520 in which a display panel 521 as a display unit and an operation
panel 522 as an input unit are integrated. The housing 502 includes
a speaker 531, microphone 532, operation unit 540, and camera unit
541. A configuration of the housing 502 is not limited thereto, and
a configuration in which the display unit and the input unit are
independent of each other may be used, and a configuration having a
clamshell structure or a slide mechanism may be used, for
example.
[0130] FIG. 20 is a block diagram showing a configuration of the
smartphone 500 shown in FIG. 19. As shown in FIG. 20, included are
as main components of the smartphone a radio communication unit
510, display and input unit 520, telephoning unit 530, operation
unit 540, camera unit 541, storage unit 550, external input/output
unit 560, GPS (Global Positioning System) reception unit 570,
motion sensor unit 580, power supply unit 590, and main controller
501. The smartphone 500 has, as a main function, a radio
communication function for carrying out mobile radio communication
via a base station device BS and a mobile communication network
NW.
[0131] The radio communication unit 510 carries out radio
communication with the base station device BS included in the
mobile communication network NW according to an instruction from
the main controller 501. Such radio communication is used to
transmit and receive various pieces of file data such as audio
data, image data and the like, and e-mail data and the like and
receive Web data, streaming data and the like.
[0132] The display and input unit 520 is a so-called touch panel
which, by way of control by the main controller 501, displays and
visually delivers to the user an image (still image and moving
picture), text information and the like, as well as detects a
user's operation on the displayed information, and includes the
display panel 521 and the operation panel 522. When a generated 3D
image is viewed, the display panel 521 is preferably a 3D display
panel.
[0133] The display panel 521 uses a LCD (Liquid Crystal Display),
an OELD (Organic Electro-Luminescence Display) and the like as a
display device.
[0134] The operation panel 522, which is placed such that an image
displayed on a display surface of the display panel 521 can be
visually recognized, is a device for detecting one or more
coordinates operated by a user's finger or a stylus. If the device
like this is operated by a user's finger or a stylus, a detection
signal generated due to the operation is output to the main
controller 501. Subsequently, the main controller 501 detects an
operated position (coordinates) on the display panel 521 on the
basis of the received detection signal.
[0135] As shown in FIG. 19, the display panel 521 and operation
panel 522 in the smartphone 500 are integrated to constitute the
display and input unit 520, and the operation panel 522 is arranged
in a manner to fully cover the display panel 521. In a case of
using such an arrangement, the operation panel 522 may have a
function to detect the user's operation also on an area outside the
display panel 521. In other words, the operation panel 522 may have
a detection area for an overlapping portion overlapped with the
display panel 521 (hereinafter, referred to as a displayed area)
and a detection area for a peripheral portion not overlapped with
the display panel 521 other than the displayed area (hereinafter,
referred to as a non-displayed area).
[0136] Note that a size of the displayed area and a size of the
display panel 521 may completely match each other, but both sizes
may not necessarily match. The operation panel 522 may have two
sensitive areas of the peripheral portion and an inside portion
other than the peripheral portion. Further, a width of the
peripheral portion is appropriately designed depending on a size of
the housing 502 and the like. Still further, examples of a position
detection method used for the operation panel 522 include a matrix
switch method, resistance film method, surface acoustic wave
method, infrared ray method, electromagnetic induction method,
electrostatic capacitance method and the like, any method of which
may be used.
[0137] The telephoning unit 330 having the speaker 531 and the
microphone 532 converts user voice input through the microphone 532
into the audio data processable by the main controller 501 to
output to the main controller 501, and decodes audio data received
by the radio communication unit 510 or the external input/output
unit 560 to output from the speaker 531. As shown in FIG. 19, for
example, the speaker 531 may be mounted on the same face as the
display and input unit 520 is provided on, and the microphone 532
may be mounted on a lateral face of the housing 502.
[0138] The operation unit 540 which is a hardware key using a key
switch and the like accepts an instruction from the user. For
example, the operation unit 540 is mounted on a lower side or lower
lateral face of the display unit on the housing 502 of the
smartphone 500, and is a press-button type switch which is turned
on when pressed down by a finger or the like and is brought into a
turned-off state by a restoring force of a spring or the like when
the finger is released.
[0139] The storage unit 550 stores a control program and control
data for the main controller 501, address data having a name,
telephone number and the like of the communication other end
associated with each other, data of transmitted and received
e-mail, Web data downloaded by way of Web browsing, and downloaded
content data, and temporarily stores streaming data or the like.
The storage unit 550 includes an internal storage unit 551 built in
the smartphone and an external storage unit 552 having a detachable
external memory slot. Each of the internal storage unit 551 and the
external storage unit 552 included in the storage unit 550 is
attained by use of a storage medium of a flash memory type, hard
disk type, multimedia card micro type, card type memory (e.g.,
Micro SD (registered trademark) memory, etc.), RAM (Random Access
Memory), ROM (Read Only Memory), and the like.
[0140] The external input/output unit 560 serves as an interface
with all external devices coupled to the smartphone 500 to allow
other external devices to be directly or indirectly connected with
the smartphone 500 via a communication or the like (e.g., Universal
Serial Bus (USB), IEEE1394, etc.) or network (e.g., Internet,
wireless LAN, Bluetooth (registered trademark), RFID (Radio
Frequency Identification), IrDA (Infrared Data Association)
(registered trademark), UWB (Ultra Wideband) (registered
trademark), ZigBee (registered trademark), etc.).
[0141] Examples of the external device coupled to the smartphone
500 include, for example, a wired/wireless head set, wired/wireless
external charger, wired/wireless data port, memory card or SIM
(Subscriber Identity Module Card)/UIM (User Identity Module Card)
card connected via a card socket, external audio and video device
connected via an audio and video I/O (Input/Output) terminal,
external audio and video device wirelessly connected, smartphone
via a wired/wireless connection, personal computer via a
wired/wireless connection, PDA via a wired/wireless connection,
personal computer via a wired/wireless connection, earphone, and
the like. The external input/output unit can deliver data received
by way of transmission from such an external device above to the
respective components in the smartphone 500 and transmit the data
in the smartphone 500 to the external devices.
[0142] The GPS reception unit 570 receives GPS signals transmitted
from GPS satellites ST1 to STn to perform positioning arithmetic
processing on the basis of the received plural GPS signals
according to an instruction from the main controller 501, and
detects a position including latitude, longitude, and altitude of
the smartphone 500. When positional information can be acquired
from the radio communication unit 510 or the external input/output
unit 560 (e.g., wireless LAN), the GPS reception unit 570 may use
the positional information to detect the position.
[0143] The motion sensor unit 580 which includes, for example, a
triaxial acceleration sensor or the like detects physical motion of
the smartphone 500 according to an instruction from the main
controller 501. Detection of the physical motion of the smartphone
500 allows a direction or acceleration of the motion of the
smartphone 500 to be detected. A result of the detection is to be
output to the main controller 501.
[0144] The power supply unit 590 supplies electrical power stored
in a battery (not shown) to each unit of the smartphone 500
according to an instruction from the main controller 501.
[0145] The main controller 501 which includes a microprocessor
operates according to the control program or control data stored in
the storage unit 550 and collectively controls the respective units
of the smartphone 500. The main controller 501 has a mobile
communication controlling function to control each unit in a
communication system and an application processing function in
order to perform audio communication or data communication via the
radio communication unit 510.
[0146] The application processing function is attained by the main
controller 501 operating according to the application software
stored in the storage unit 550. Examples of the application
processing function include, for example, an infrared communication
function to control the external input/output unit 560 to perform
the data communication with an opposite device, e-mail function to
transmit and receive an e-mail, Web browsing function to view a Web
page, and the like.
[0147] The main controller 501 has an image processing function to
display a video on the display and input unit 520 and so forth on
the basis of the image data such as the received data or downloaded
streaming data (data of still image and moving image). The image
processing function refers to a function that the main controller
501 decodes the above image data and subjects a result of decoding
to image processing to display the image on the display and input
unit 520.
[0148] Further, the main controller 501 performs display control of
the display panel 521 and operation detecting control to detect the
user's operation input via the operation unit 540 and the operation
panel 522.
[0149] The main controller 501 performs the display control to
display an icon for starting the application software or a software
key such as a scroll bar, or display a window for creating an
e-mail. Note the scroll bar refers to a software key for accepting
an instruction to move a displayed portion of an image such as a
large image not entirely accommodated within the displayed area of
the display panel 521.
[0150] The main controller 501 performs the operation detecting
control to detect the user's operation input via the operation unit
540, accepts via the operation panel 522 an operation on the above
icon or an input of a character string to an input field in the
above window, or accepts a request input via the scroll bar for
scrolling of the displayed image.
[0151] Further, the main controller 501 has a touch panel
controlling function to perform the operation detecting control to
determine whether an operated position on the operation panel 522
is the overlapping portion (displayed area) overlapped with the
display panel 521 or the peripheral portion (non-displayed area)
not overlapped with the display panel 521 other than the
overlapping portion, and control the sensitive area of the
operation panel 522 or a displayed position of the software
key.
[0152] The main controller 501 can also detect a gesture operation
on the operation panel 522 and perform a predetermined function
depending on the detected gesture operation. Instead of a simple
touch operation of related art, the gesture operation means an
operation including tracking by a finger or the like,
simultaneously specifying a plurality of positions, or combining
these operations to track from at least one of a plurality of
positions.
[0153] The camera unit 541 is a digital camera electronically
imaging by use of the image pickup device such as a CMOS
(Complementary Metal Oxide Semiconductor) or a CCD (Charge-Coupled
Device). The image pickup device 10 described above can be applied
to the camera unit 541. The image pickup device 10 can capture the
wide angle image and the telephoto image with no need for the
mechanically switching mechanism or the like, and thus, is
preferably used as the camera unit which is built in a thin
portable terminal like the smartphone 500.
[0154] The camera unit 541 can under the control by the main
controller 501 convert the image data obtained by capturing an
image into a compressed image data such as JPEG (Joint Photographic
coding Experts Group), for example, to store in the storage unit
550 and output via the input/output unit 560 or the radio
communication unit 510. In the smartphone 500 shown in FIG. 19, the
camera unit 541 is mounted on the same face as the display and
input unit 520, but, a mounted position of the camera unit 541
being not limited thereto, may be mounted on a rear face of the
display and input unit 520, or a plurality of camera units 541 may
be mounted. In the case where a plurality of camera units 541 are
mounted, the camera unit 541 for imaging may be changed over for
singularly imaging, or a plurality of camera units 541 may be
simultaneously used for imaging.
[0155] The camera unit 541 can be used for the various functions of
the smartphone 500. For example, an image obtained by the camera
unit 541 may be displayed on the display panel 521, or an image of
the camera unit 541 may be used as one of operation input on the
operation panel 522. When the GPS reception unit 570 detects a
position, the position can be detected by referring an image from
the camera unit 541. Further, by referring an image from the camera
unit 541, without using the triaxial acceleration sensor or in
combination with the triaxial acceleration sensor, an optical axis
direction of the camera unit 541 of the smartphone 500 can be
determined, and also a current usage environment can be determined.
Of course, an image from the camera unit 541 may be used in the
application software.
[Others]
[0156] The reflective mirror in the reflective mirror type lens
configuration in the first and second embodiments of the
photographing optical system is not limited to a concave mirror and
a convex mirror, but may be a planar mirror, and the number of the
reflective mirrors is not limited to two, but three or more
reflective mirrors may be provided.
[0157] In the photographing optical systems in the embodiments, the
wide angle lens is used for one of the central optical system and
the circular optical system and the telephoto lens is used for the
other, but, not limited thereto, one of the wide angle lens and the
telephoto lens may be a normal lens, and further, the central
optical system and two circular optical systems having a diameter
different from each other may be disposed to give the wide angle
lens, the normal lens, and the telephoto lens to the respective
optical systems.
[0158] As the pupil division device for making the directional
sensor have pupil directivity, not limited to the pupil image
separation method and light shielding mask method shown in FIG. 6,
but those using a pupil division polarization element and the like
may be applied.
[0159] Further, a lens shared by the central optical system and the
circular optical system or a movement mechanism for moving the
directional sensor in the optical axis direction may be disposed to
carry out focusing thereby.
[0160] It goes without saying that the present invention is not
limited to the embodiments described above and may be modified in
the scope without departing from the spirit of the invention.
* * * * *